Bolster swing-damper.



No. 872,014. PATENTED NOV. 26, 1907. w. G. PRICE.

BOLSTBR SWING DAMPER. APPLICATION FILED AUG. 18, 1906.

FIG.1

WITNESSES.

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WILLIAM G. PRICE, OF NEW CASTLE, PENNSYLVANIA.

BOLSTER SWING-DAMPER.

Specification of Letters Patent.

Patented Nov. 26, 1907.

Application filed August 18.1906. Serial No. 331.13?

T 0 all whom it may concern:

Be it known that 1, WILLIAM G. PRICE, a resident of New Castle, in thecounty of Lawrence and State. of Pennsylvania, have invented a new anduseful Improvement in Bolster Swing-Dampers, (Case 1;) and I do herebydeclare the following to be a full, clear, and exact descriptionthereof.

This invention relates to railway trucks, and more especially toelectric motor trucks for street railway and similar service.

Theo bject of the invention is to provide means for damping or checkingthe endwise movement of swinging bolsters such as are ordinarily used intrucks of this type, in order to provide an easy riding truck.

' On most motor trucks the bolsters supporting the car body are mountedto have 0th a vertical and end-wise movement in the truck frame, thisbeing accomplished in various ways, principally by su porting thebolster upon elliptic springs ield by socalled bolster hangers, whichswing to permit endwise movement of the bolsters, so as not to give toosudden movements to the car body when rounding curves, on rough track,and the like. If the bolster has too much endwise swing it will strikeagainst the side frames, thus causing a blow which is disagreeable tothe passengers. Consequently, it has heretofore been the practice toprovide means which checks the swinging movement of the bolster beforeit strikes the side frames, such checking means being generally referredto as damping" means.

It is highly desirable that only slight impulses on the part of thebolster to move endwise should not be restricted, or at least onlyrestricted to a very slight extent so as to give an easy riding truck,but that tendencies of the bolster to swing to a greater extent shouldbe restricted, and the resistance should keepon increasing as thebolster continues to swing outwardly.

The special object of thisinvention is to provide bolster swing dampingmeans which attains the object just stated, namely, to give a free oronly slightly impeded swinging 'movement to the bolster through smallamplitudes, but to give an automatically increasing resistance as thebolster continues to swing outwardly. This object is accomplished by thearrangement of friction mechanismhereinafter described and claimed.

In the accompanying drawings Figure 1 is a plan view of a portion of atruck frame and bolster provided with my invention; Fig. 2 is atransverse section on the line 22 Fig. 1 Fig. 3 is a horizontal sectionon the line 3-3 Fig. 2; Fig. 4 is a similar view showing a modification;Fig. 5 is a erspective view of the friction plate; and Fig. 6

is a perspective view of one of the washers.

The truck frame may be of any suitable type, that shown having sideframes connected by transoms 2 whichare shown as sections of angle bar.The frame is rovided with bolster hangers 3 carrying elliptic springs 4upon which the bolster 5 rests. It is obvious that this manner ofmounting the bolster tically y compression of the springs, and end-wiseby the swinging of the hangers. This type of bolster is known in thetrade as a swing bolster. The bolster may be of any desired type, thatshown being a truss having a bottom chord 6 and to chord 7.

My improved friction mec ianism includes a plate or plates having oneend in frictional engagement with the bolster and its op osite end infrictional engagement with the frame,

preferably the transom, said frictional engagement being automaticalladjustable. In Figs.1 to 6 this friction mec anism is shown as a singleplate 10 arranged in the space between the bolster and the transom andextendin longitudinally of the bolster. At one end the plate is rovidedwith a short slot 11 through whici passes a bolt 12, which extendsthrough the vertical u -turned portion 13 of a plate 1.4 secured to t 1ebottom member 6 of the bolster by means of bolts 15. Interposed betweenthe plate 10 and head of the bolt 12 is a washer 16. The inner end ofthe boltis provided with a nut 17 and cotter pin 18, and between the nutand the upturned portion 13 of the plate is a spiral spring 19 which isnormally under compression and acts to yieldingly draw the bolt inwardlyso that the plate 10 is frictionally held between the upturned late 13and washer 16. The opposite en of the plate is provided with a lon slot20, preferably 0 ening on the end of t e plate so as to facilita'teremoval and replacement, through which slot passes a bolt 21 which-alsoextends through an opening in the transom 2 and having on its inner enda nut 22 and cotter pin 23. Washers 24 are laced on the bolt 21 on bothsides of the p ate 10. Sur- 110 v ermits the same to move bothverrounding the bolt between its nut 22 and the transom 2 is the spiralspring 25 which is normally under com ression and which serves tofrictionally 0 amp the plate 10 between the washers 2.4. ,Preferably thespring 25 will be stronger than the'spring 19 so that a greater frictionis exerted on the outer than on the inner end of the plate 10.

When the bolster begins to move end-wise the late 13, bolt 12 and washer16 are necessari y carried with it. Consequently this endwise movementof the bolster is resisted by the friction between the plate 10 and thewasher 16 on one side and plate 13 on the other. The amount of thisfriction can be adjusted by adjusting the nut 17 on the bolt 12, and canbe made as light as desirable so as to give only a slight damping effecton the initial swinging movements of the bolster. As soon, however, asthe swinging movement of the bolster has reached such an amplitude thatthe bolt 12 reaches the end of the slot 11, the late 10 is carried withthe bolster, thus ut' izing the friction at the outer end of said plate,between it and the washers 24, for checking or damping this endwisemovement, and as the friction here is much greater than at the inner endof the plate, due to the greater stren th of the spring 25, there is aproportionate ygreater resistance to the endwise movement of the bolsteras it swings outwardly, thus checking said outward movement before .thebolster strikes the side frame. The friction device therefore gives thedesirable result of a very light resistance to only slight endwisemovements of the bolster, with increasing resistance to greater end-wisemovements of the bolster.

By using a number of plates side by side as shown at 10, 10 and 10 Fi.4, with washers 26 interposed between the p ates, said plates beingsecured by means of the same bolts as above described, but having slots11 of different lengths as indicated at 11, 1 l -and 11 it is obviousthat a number of increases of friction may be obtained for a very longswing of the bolster. The beginning of the swing is resisted merely bythe friction at.

movement of the bolster endwise, but comparatively small resistance tothe movement of the bolster vertically. The plate 10 is so long that thebolster has a long leverage, which readily overcomes the rotary frictionat the bolts 12 and 21, which arises when the bolster movements arevertical. Should the prevent said plate from becoming twisted.

To revent wear on the bolt 21 I prefer to turn t e upper and loweredgesof one of the washers 24 inwardly as shown at 28. The

late 10 rides on one of these flanges and ence does not rub against the.bolt. As a tion screwed into the transom. A co lar 30 surrounds theouter end of this sleeve and transmits the pressure of the bolt head tothe washer 24.

What I claim is:

1. In a car truck, the combination of the truck frame, a bolster mountedtherein for both vertical and endwise movement, and friction mechanismbetween the bolster and truck frame and arranged to resist endwisemovement of the bolster with increasing.

and arranged to give automatically increas- 1 ing friction as thebolster moves outwardly.

4. in a car truck, the combination of the transoms, a bolster mountedbetween the transoms for both vertical and endwise movement, and afriction plate having at one end frictional connection to the be sterand at its opposite end frictional connection to the transom.

5. In a car truck, the combination of a truck frame, a bolster mountedtherein for both vertical and endwise movement, a friction plate havingan adjustable frictional connection at one end of the bolster and anadjustable frictional connection at its oppo site end to the frame.

6. In a car truck, the combination of a truck frame, a bolster mountedtherein for endwise movement, a plate having a limited frictionalsliding connection with the bolster and having its 0 posite end infrictional engagement with t e frame.

7. In a car truck, the combination of a frame, a bolster mounted thereinfor endwise movement, a friction plate connected to the bolster by aslot and pin, and having a fricfurther precaution the bolt may besurrounded by a sleeve 29, shown as a short pi e sectional slidingengagement at its opposite end with the frame.

8.. In a car truck, the combination of a frame, a bolster mountedtherein for endwise movement, a late having a slot and bolt connectionwit the bolster, a washer on the bolt bearing against the plate, aspring on i the bolt for pressing the Washer and plate together, and theopposite end of said plate aving a frictiona sliding connection with theframe. I

'9. In a car truck, the combination of a frame, a bolster mountedtherein for endwise movement, a friction plate having a limited slidingfrictional engagement With the bolster, the opposite end of the platehaving a slot andbolt connection with the frame, and a springsurrounding the bolt for pressing the plate against the frame. 10. In acar truck, the combination of a I frame, a bolster mounted therein forendwise movement, a friction plate having a slot and bolt connectionwith the bolster at one end, a spring surrounding the bolt forfrictionally pressing. the plate against the bolster, said late at itsopposite end having atslot and bolt connection with the frame, and aspring surrounding the bolt for frictionally pressing the plate againstthe frame.

11.- In a car truck, the combination of a frame, a bolster mountedtherein for endwise movement, a friction late engaging the bolster, theop osite en of the plate having a slot and b0 t connection with theframe, a sleeve surrounding the bolt, and a spring arranged to press thelate against the frame.

12. In a cartruoli the combinatino of a frame, a bolster mounted thereinfor endwise movement, a friction plate engaging the bolster and having aslot and bolt connection With the frame, a washer on the bolt havingflanges on its edges to support and guide the plate, and a s ringarranged to press the plate against t I e frame.

In testimony whereof, I, the said WILLIAM G. PRICE, have hereunto set-myhand.

WILLIAM PRICE.

Witnesses:

M. D. VOGEL, F. W. WINTER.

